An ultrafine three-dimensional nanofiber network structure of a very high porosity endows bacterial cellulose (BC) to function as support for heterogeneous catalysis. A novel catalyst of BC supported alumina (Al2O3) was developed by soaking purified BC hydrogel in aluminum nitrate (Al(NO3)(3)) aqueous solution, dehydration (hot air drying and freeze-drying) and calcination. The Al/BC catalysts reveal interior meso-macro porous structures with average pore diameters in the range of 17-34 nm. The catalytic activities were examined through an ethanol dehydration reaction in the gas phase at atmospheric pressure in the range of 200-400 A degrees C. The effects of acidic metal loading and dehydration methods were investigated. Increasing Al loading from 12 to 50% resulted in a decreased surface area but an increase in pore size. At the same Al loading, the catalysts with a dehydration process by hot air drying presented higher Al concentrations on the outer surface compared with those by freeze-drying. At high temperature of 400 A degrees C, Al/BC catalysts with 25 wt% Al loading and dehydrated by freeze drying (25Al/BC FD) and 50 wt% Al loading, dehydrated by hot air drying (50Al/BC TD) exhibited the highest ethanol conversions of 65.7-66.4% and ethylene yields of 43.26-44.24%, respectively, whereas at low temperature of 200 A degrees C, Al/BC catalysts with 25 wt% Al loading with either dehydration method exhibited the highest diethyl ether yields of 40.02-41.60%. [GRAPHICS] .